Wait a second, is that 211 ppm in the 2 gallons?
That would explain why it's becoming a problem with such a small addition.

That would only be 84 ppm in 5 gallons. As far as too much calcium, I don't think that would be an issue in the mash, only the possibility of tasting it in the final beer. So, if that's the case, I think 4 tsp should be fine.

Either way, if you can monitor your pH, the best approach is to add a fraction of the CaCO3 and add more as necessary to hit your pH.

Well I brewed the stout Friday night and I started with 2 tsp of calcium carbonate. I checked my PH and indeed it was still a little high. I added one more tsp and it appeared to be around 5.8. I was satisfied with that since I was taking seriously the warning of not adding more that 1.5 tsp per gallon of mash water. Although, I still think I could have gotten away with another tsp as you said slothrob.

WOW, it was an INCREDIBLY tasting wort prior to pitching yeast! I could have just drank that as it was so good.

You would add CaCO3 when mashing an acidic malt mixture, like the roasted malts in a Stout or Porter, with low alkalinity water. The water along the coasts of the US is often very low alkalinity with little-to-no CO3 and little buffering capacity. The combination of that type of water and darkly roasted malts can drop your mash pH below it's optimum.

Mashing below pH 5 (at mash temperature, 5.3 at room temperature) can dramatically reduce your mash efficiency and the attenuation of your beer. Low pH can also make a beer taste sour. In my hands, dark beers mashed at the proper pH seem to come out less harshly roasty, though I'm not sure why. It may be a personal taste preference against a roasty beer that is also tart. It might also be related to the higher Na and Cl I get by adjusting the pH.

But I think you probably know all that from Siebel, Brewforbeer.
Why would you never add CO3?

hangtendesign wrote:Well I brewed the stout Friday night and I started with 2 tsp of calcium carbonate. I checked my PH and indeed it was still a little high. I added one more tsp and it appeared to be around 5.8. I was satisfied with that since I was taking seriously the warning of not adding more that 1.5 tsp per gallon of mash water. Although, I still think I could have gotten away with another tsp as you said slothrob.

I'm glad it tasted good!

One thing, calcium carbonate raises the pH. So if it was a little high you wouldn't want to add any more calcium carbonate. pH 5.8 at room temperature is fine, though. I believe 5.5-5.8 (at room temperature) is thought to be ideal.

Interesting what you said about raising the PH. So you are saying that dark roasted grains lowers the PH and I was adding it to raise the PH? I checked my PH with those strips. Seemed to work pretty well but it wasn't room temp. It was mash temp.

I simply have never had to add carbonate... I am always trying to remove it... Glad you made me think about it though.

Reading carbonate in or near the triple digits ppm-- on purpose-- made me question it...

Distilled water and pale malt give you a typical PH of 5.8 which I consider to high for various reasons. When deciding upon my water make up getting the PH down--- has always been the problem for me even when using RO water.

Certainly making a stout with lots- more then 10% or so of roasted malts could lower your PH below the ideal, add some crystal and yeah-- it's a good point to think about... You may end up raising the PH just to lower again later though- i don't like more work then i have to...

Malt has good buffering capacity but the PH can rise as you sparge as the buffering is diminished-- which is both counter productive to my goal of 5.2 PH in the boil kettle and also can cause the release of bittering compounds from the husk of the grain if you are trying to be efficient.

Carbonate exasperates this problem by not allowing the PH to lower as well...

Although if you desire a higher PH certainly adding carbonate will do so-- it is twice as effective at raising PH as calicium is at lowering it. By all means do so if that produces a beer you desire.

Some guidelines I have followed with success are:

No more then 75ppm carbonate for all beers, no more than 50ppm for light beers.

Brewing Water Adjustments:
- First step: Add calcium salts to meet calcium requirements for brewing
- Objective is 40 to 60ppm in finished beer
- Needed for enzymes, especially alpha amylase
- Precipitates calcium oxylate to prevent gushing
- Yeast flocculation
- Can reduce mash and wort PH
Malt has 30ppm calcium but half calcium is lost brewing process! Must end up with 40ppm in the end wort.

Hangtendesign: Would you mind posting a copy of your recipe... Your beer will be fine-

But I am not clear either-- are you adjusting the PH to change the color of the beer? Or the taste? Or both? Acidic and astrigent could be percieved by taste as similar but you would change your recipe/water profile and/or proceedure differently to adjust.

Those charts-- i just kind of looked at -- are based on 100% base malt... and the link to SRM is inconsequential unless you are brewing a very light colored beer.

From my calculations, your water untreated is very good, with 10% dark roasted malt will give you a PH just under 5.3...

1) If it was me I would leave well enough alone. Anything around 10% roasted malt will make your beer plenty black. I would at least try a batch like that. Why monkey around?... Unless this is a subsequent batch and you are monkeying around for reasons?

2) If adding dark crystal malts or more then 10% roasted malts then you could add chalk to keep the PH up over 5.3 or whatever you are shooting for.

3) You could add calcium chloride and chalk and gypsum to change the mouthfeel of the beer. Make it more slick and coating with chloride. By adding gysum and calcium chloride to the water until the chloride and sulfate levels were around 100 or so and in about a 1 to 1 ratio. More chloride more mouthfeel. Don't over due it. Then add chalk to raise PH back up to 5.3 or whatever you desire.

4) If it's a dry irish stout you could add gypsum (up around 300 ppm or so)to bring out a smoother bitterness and then chalk if necessary to raise PH to 5.3.. Change hoping rates maybe as well?

All these calculations can be figured out before hand. Treat all mash and sparge water. Then test and adjust mash water if needed for PH as they are estimates.

5) You could change the yeast you are using, pitching rates, and/or the temperature you are fermenting to adjust as well.

My point being-- there's lots of things you could do and you may want to look at and conspire with others about the recipe and proceedure as a whole to achieve your goals. But carbonate is generally avoided for lots of reasons (inhibits the action of enzymes, slower lautering, lower extract yield of the malt, less yeast growth, slow fermentation, produces harsh astringent flavor (polyphenols), high bitterness yield, more beer haze, increases PH in wort, harsher perceived bitterness) and i would not add more then you need. Breweries can spend lots of money removing it...

hangtendesign wrote:I checked my PH with those strips. Seemed to work pretty well but it wasn't room temp. It was mash temp.

Mash pH is a bit confusing, for a number of reasons. You want a mash pH of >5.0 to <6.0, ideally more like 5.1 to 5.5 at mash temperature.

However, in almost all cases, the method used to measure pH will be more accurate at room temperature. That includes pH strips, which are calibrated for a room temperature measurement.

However, wort pH drops about 0.3 pH points going from room temperature to mash temperature. That means that your approximately room temperature mash sample's target pH is 5.4-5.8. A pH of 5.3 is very nearly the lowest this sample should measure, since mash efficiency and attenuation will begin to suffer below this pH, due to inhibition of mash enzyme activity.

John Palmer gave an excellent presentation comparing the benefits of proper water on beer quality. The benefits of raising carbonate levels for the mash pH of a dark beer were clear. The experiment also convinced the experimenters of other flavor benefits, as well. Some of these issues, like a harshness to the roasty character of stouts, were ones I had brewing these beers with a low Residual Alkalinity water. It would depend on what you wanted from your beer, I suppose.

Brewforbeer, most of the disadvantages you list for carbonates are disadvantages of a high pH or a low calcium concentration. This is why carbonate additions should be matched to beer color and would be inappropriate for a pale beer. Also why carbonate levels need to be matched to calcium levels, which is one benefit to calcium carbonate over sodium bicarbonate, in general.

I successfully added two teaspoons of chalk last Friday night since I added it directly to the mash. It worked perfectly just as slothrob said. I never tried to dilute it in water but instead directly to the mash as was suggested in the beginning of this post.